GB 2284427 A describes chlorine-containing, symmetrically disubstituted triphendioxazine compounds of the following general formula ##STR2##
where
the rings labelled A carry rings which are fused linearly or angularly and consist of radical members, inter alia, of the formulae --NR.sub.1 --(CO).sub.m --NH-- and --CR.sub.1.dbd.CH--CO--NH-- wherein R.sub.1 is hydrogen, C.sub.1-4 alkyl or phenyl, preferably hydrogen, methyl or ethyl; and m is 1 or 2.
The preparation process disclosed in GB 2284427 A starts from intermediates i.e. amino compounds, which are ortho-substituted by an alkoxy group and are obtainable only by way of a relatively complex synthesis. The pigments disclosed in GB 2284427 A are difficultly dispersible and cannot easily be brought into pigment form.